Use of an absorbable mesh to repair contaminated abdominal-wall defects.

When polypropylene mesh (Marlex) is used to repair contaminated abdominal-wall hernias, a high incidence of mesh-related chronic infection, drainage, erosion, and bleeding is noted. As an alternative to placing polypropylene mesh in a contaminated field, in the past 18 months we have used an absorbable polyglycolic acid mesh (Dexon) to repair contaminated abdominal-wall defects in eight patients--three with necrotizing abdominal-wall infections, one with an extensive electrical burn of the abdominal wall, three with infected polypropylene mesh from a previous repair, and one whose hernia was covered by a chronically infected scar. In seven of the eight cases, a single sheet of polyglycolic acid mesh was sewn to the fascial margins. In four cases, skin was closed over the mesh; wound packing and subsequent skin grafting were required in the other four. In follow-up studies that ranged from three to 18 months, six of the eight patients developed abdominal-wall hernias at the site of absorbable mesh placement. None of the patients required an abdominal binder. Postoperative hernia development is probable in patients whose defects are repaired with absorbable mesh. However, this complication is balanced against the more serious complications of fistula, bleeding, skin erosion, drainage, and chronic infection, which require removal of the more rigid nonabsorbable meshes in 50% to 90% of cases when the latter are placed under contaminated conditions. Placement of absorbable mesh for temporary abdominal-wall support until wound contamination resolves enhances the likelihood of subsequent successful placement of a permanent mesh.

Cardiac tamponade caused by pulmonary artery perforation after central venous catheterization.

We report a case of pulmonary artery perforation with resultant cardiac tamponade after central venous catheterization and review six previously reported cases. Tamponade may be an acute or late complication and is usually associated with the effusion of intravenous fluid into the pericardium. Three cases actually occurred after catheterization through the "safer" peripheral venous access route (basilic vein). The diagnosis of perforation and tamponade as well as the treatment can be accomplished using the catheter. Recognition and appropriate treatment of this rare complication may avoid significant morbidity and mortality.

Dose-dependent effects of nalbuphine in canine hemorrhagic shock.

We noted the effects of the mixed opiate agonist/antagonist nalbuphine on cardiovascular function and survival in canine hemorrhagic shock. Anesthetized adult mongrel dogs were bled to a mean arterial pressure (MAP) of 45 mmHg, which was maintained with a reservoir for 1 hr before the reservoir was clamped and the animals treated with 0.9% NaCl as a control or nalbuphine at various doses. Shed blood was reinfused 1 hr after the reservoir was clamped, and survival was followed for three days. Nalbuphine at 1-4 mg/kg bolus plus 1-4 mg/kg hr infusion intravenously for 3.5 hr increased MAP, cardiac output, left ventricular contractility, heart rate, and survival. At doses above 8 mg/kg plus 8 mg/kg hr nalbuphine had deleterious effects on these parameters and survival. These effects were dose-dependent and support the hypothesis that endorphins acting on opiate receptors contribute to the cardiovascular pathophysiology of canine hemorrhagic shock. Nalbuphine, furthermore, may be a logical alternative to naloxone, since its analgesic properties obviate the theoretical objection of enhanced pain perception with the use of naloxone in shock.